As you may have guessed from my other posts, I hold West End Games (developer of the Star Wars D6 RPG) in very high regard. They produced a wonderfully rich and playable game based on my favorite movie series—and opened enough doors through their products to ensure that I had YEARS worth of material to help build my campaign. But as much as I love them, there was one thing that got to me over my years of using their materials, and that was their occasionally erratic stat system for various vehicles and even characters.
As far as vehicle stats went, the damage code for weaponry was all over the place. You had laser cannons that did from 2D to 4D damage, Turbolasers that did from 2D to 5D, etc. You can explain some of that away, of course, as different models of lasers, but... well, you'd think there would be some kind of standardized naming system like.. 'light' laser cannon for the 2D variety, etc. And then there was the Nebulon-B escort frigate that was.. well a complete piece of crap based on its game stats—completely under-gunned for the role it was apparently supposed to fill. A hull of 3D+2? A Corvette, half that size, had a 4D hull. 12 4D turbolasers? 12 2D laser cannons? That means it can't duke it out with bigger ships.. and it can't duke it out with starfighters, either. The Imperial sourcebook threw another wrinkle into things by declaring (for some reason) that the 20m long Skipray Blastboat and 30m long Gamma shuttles were 'Capital Scale'...which.. means that the Gamma actually had the same hull strength as a Nebulon-B...
This kind of stuff just made no sense, and in my campaign I quickly adopted a standardized system of weaponry and weapon damage and wound up revamping the hull codes on just about every capital ship out there, as well as many other small craft.
Character statistics were rather erratic as well. The feature characters (Luke, Han, etc.) were (I thought) rather well done. They had a broad variety of skills. Some at a very high level, others at modest but usable. Yes, they were a bit bogus. But that's fine. They're the 'Big Heroes' of the setting—and were something to aspire to. But in a lot of the sourcebooks, the supporting NPCs were completely sketchy and downplayed. The best example of this was one of my favorite characters: Wedge Antilles. The first stats presented for him had him having a 5D piloting skill (or thereabouts) at the battle of Yavin. Luke, by comparison, had around a 7D skill. From what I saw in the movies, Luke wasn't THAT much better of a pilot than Wedge (witness Wedge bailing him out of a dogfight). 6D probably would have been a respectable level for Wedge then. Okay, so they weren't very far off in their stats. But then you got the Return of the Jedi sourcebook...and according to that, after four years of constant combat and promotion to the command of one of the fighter wings at the battle Wedge had... a 6D piloting skill. Ridiculous. Wedge wasn't the only under-powered NPC in those books and the discrepancies only widened with further supplements.
Of course all of this can be explained away by the simple fact that many people were involved in writing and producing this game. And not all of them compared notes before things were published. I can also say that none of this really prevented me from enjoying the game, either. In fact, I kind of liked the exercise of bringing the various vehicles and peoples 'up to code' in my own system. I just think it is something that should be pointed out to GMs and players using the D6 system. If you're okay with the erratics, then no worries. But if you like a bit more logic in your stats then you may have some finagling to do.